New directions in cancer research are leading investigators to consider increasingly complex theories and methodologies for studying cancer etiology, progression, treatment, and prevention. Especially important is the recognition of psychosocial, environmental, and genetic factors. The integration of such factors in cancer research requires increased sophistication in biostatistical theory and methods. The goal of the proposed biostatistical core is to insure that cancer center researchers have access to statistical expertise in the design of studies and in the analysis of data arising from them. The specific aims are to: 1) Develop a shared resource in biostatistical consultation (in study design and statistical analysis); 2) Provide educational opportunities in biostatistical methods (through a didactic course in biostatistical methods, an ongoing research seminar/journal club, and quarterly workshops/symposia); and 3) Identify areas for the development of new statistical methods. The Core will be available to all Cancer Center faculty and trainees. Core members will include biostatisticians with established track records (through prior collaborations with Cancer Center researchers) in the application of biostatistical methods in basic science and clinical medicine. A policy of prioritization of requests for usage of the Core has been developed. Mechanisms will be established to document all activity by Core members, and a computerized reporting system will generate monthly and quarterly summary reports of Core activity to assist the Facility Leader and Advisory Committee in their review of facility utilization.